In recent years, methods and apparatus which use lasers to manufacture semiconductor devices have been developed. Examples of these methods and apparatus include laser etching, or laser scribing, in which films are etched and patterned, laser annealing in which the crystalline state of films or their surfaces are changed by laser irradiation, and laser doping in which an impurity is diffused into films or their surfaces by laser irradiation within an ambient containing the impurity.
In these conventional semiconductor fabrication methods using lasers, a substrate already processed by other film formation apparatus or etching apparatus is first placed in position inside a laser processing apparatus. The inside of this apparatus is evacuated and the substrate is heated and then the substrate is processed by laser radiation. Consequently, the productivity is very low.